Gear-grinding device.



R. B. WEAVER.

GEAR GRINDING DEVICE.

APPLICATION FILED mlm, 1912.

' Patented July 1'6, 1,912.

3 SHEETS-SHEET 1.

R. B. WEAVER.

GEAR GRINDING DEVICE.

APPLICATION HLED 1113.6, 1912. l

Patented July 16, 1912. 1

v 3 SHEETS--SHEBT 2.

R. B. WEAVER. GEAR GRINDING DEVICE.

APPLICATION FILED FEB.6, 1912.

Patented July 16, 1912.

lUNITED STATES PATENT ornicn.

ROBERT R. WEAVER, or DETROIT, MICHIGAN, AssIeNoR To' THE TI'MKEN-DETnoiT AxLE COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OE OHIO.

GEAR-GRINDING DEVICE.

Specification of Letters latent.

'Patented Juiyie, 1912.

Application filed February 6, 1912. Serial No. 675,824.

To all whom 'it may concern: v

Be it known that I, ROBERT B. WEAVER, a citizen of the United States, and a resident. of the city of Detroit, in the county of Vayne and State of Michigan,l have invented a new and useful Improvement in Gear-Grinding Devices, of which the following is a specification. This invention relates to devices for grinding andfinishing gears and more particularly those constituting worm or screw gearing and spiral gears and the like..

It has forits principal objects to produce a machine by the use of which the high spots on the teeth and rubbingsurfacesA of inter- Ineshing gears may be eliminated without materially affecting the low spots.

he invention consists in the parts and in the arrangements and combinations of parts hereinafter described and claimed.

i In the accompanying drawings .which form part of this specification land wherein like .symbols refer. to like parts wherever they cccur,-Figure 1 is a top plan view of av machine illustrating an' adaptation of the invention; Fig. 2 is a side elevation; Fig. 3 is an end elevation; Fig. '4 is a section taken on the line 4-4 of Fig. 2; Fig. 5 is a section taken on the line 5 5 of Fig. 3; Fig. 6 is a perspective view of the cradle* which carries the worm to be ground;F ig. 7 is a perspective view of the removable-bearing block;

and Fig. 8 is a perspective View of the stubshaft.

rEhe machine illustrated in the drawings comprises a body casting or base 1. A. master worm or screw-gear 2 is fastened on a shaft 3 and meshed with a worm-wheel 4 fixed on a shaft 5. This gearing is housed in a closed chamber 6 so that dust is eX- cluded and the gears may be run in oil if desirable. The shaft 5 rotates in an eccentric bore in a bushing 7 rotatably fitted in the body casting 1 and' locked in place by a set-screw 8. By turning `the bushing 7 the gears 2 and 4 are'adjusted in mesh so that all back lash is taken up, which is necessary as will hereinafter more fully appear. To

.facilitate such adjustment the bushingis provided at its end with a collar portion 9 having a peripheral recess or recesses 1Y0 for the application of wrench. v

The worm-wheel 11 to be ground is an eX- act duplicate of the master worm-wheel. @hat is, in so far as the tooth arrangement is concerned.A The shaft 5 is 'arranged so that the worm-wheel 11 can be readily attached and detached. It is' obviously provided with a spline. or key, 12; a screwthreaded collar or annular enlargement 13 on which is fitted a clamping and adjusting ring 14 having a peripheral recess vor recesses 15 for the application of a wrench; and4 its end portion is reduced, as. at" '16', and screw-threaded to receive a securing.;v nut '17.' A washer 18 is interposedbetween the', nut and the worm-wheel and it is. slotted, as at 19, so that it may' be' removed'` without removing the nut entirely from the shaft; the nut being small enough to allow the wrmwheel to slip over it'. y

The worin or screw. 20 to be ground is re; movahly attached onaspindle 21,*for which, purpose the; latter is provided. with a fixed collar 22l and .anopposed removable screwthreaded collar or clamping ring 23. The spindle is provided' at one end' with a vtaper shank 24 fitted tight in agcounterpart axial socket in a stub-shaft 25 journaled in a cradle or pivoted open framev 26. The opposite end portion of the spindle is reduced in diameterand journaled in a bearing block 27 iitted slidably between the end portions. of the, side members '28 ofthe cradle. -This block is provided with ribs 2 9 which slide in undercut grooves 30 provided in the innerl faces .of said members 28; and itrests on the connecting web 31.

The cradle 26 is providedwith trunnionsv screw-threaded to receive a screw`38 which '19@ bears against the under side of said iiange 37. Journal/ed in abraoket extension 3 9 on the base 1 is a shaft 40 having a driving pulley 41 fixed thereon. 4This shaft has a pinion 42 Xed on it meshingwith a g'ear- 43 fixed on m5 the-shaft 3 and a like gear 44 on the stub- 'shaft 25, the teeth-.of saidpinion and gears l being accurately formed and meshed .so as to run without any backlash.-

"l 'ie inner of the stub-shaft 25, as M6 more clearly shown in Fig. 8, is provided .vith a thrust collar 45 and its projecting outer end portion is reduced in diameter to provide a shoulder 46 against which the gear 44 abuts. The gear 44 thus serves as a thrust member' opposed to the collar 45. The gear 44 is provided with a split hub portion 47 and locking-screw 48, so that it may be releasably clamped on the stub-shaft 25 in order to be slid out of mesh with the pinion 42 to raise the cradle 26 high enough to facilitate the placing or removal of the spindle 21 and worm 20 carried thereon. A collar 49 is provided to serve as a stop to hold the gear 44 on the stub-shaft While the cradle is tilted.

'When the shaft 40 is rotated the pinion' 42 actuates the 'gears 43 and 44 in one direction and at the same speed, and consequently the shaft 3 and spindle 21 are rotated simultaneously at a like speed and, of course, the master worm 2 and worm 20 to be ground are thereby positively driven at the same velocity. The worm-wheel 4 being in snug mesh with the worm 2 is driven without any backlash, and the worm-wheel l1 to be ground being ixed on the shaft 5 rotates positively with said wormewheel 4. Therefore, the worm 20 and worm-wheel 11 are revolved by' means external of themselves at a continuously correct velocity ratio irrespective of any high or low spots on their cooperating rubbing faces. By sprinkling or otherwise applying emery or other abrasive material on the gears to be ground, while'they are being thus rotated, the touchA ing high spots are gradually worn down without 'affecting 'the low spots. At the beginning, the cradle is lowered until the Worm Q0 is brought into'mesh with the worm-wheel 1 1 so that the highest spots touch, and after the worm has run in this position for a while it is adiusted into closer mesh until other high spots touch, and so on until a uniform and smooth bearing is had all over the rubbing faces. The adjustment is etl'ected by manipulating the screw 38 which Works on the stud 34. Obviously, therefore, this uniform bearing will then represent an absolutely invariable and correct velocity ratio between the worm and Worm-wheel which have thus. been ground.

Instead of sprinkling or flowing the abrasive material onto the gears, the material may be filled into the chamber 50 in which theI Worm-vvheel 11 runs, to be taken up by the teeth of the worm wheel. This chamber is provided With a removable side plate or door 51 having marginal notches to tit upon ieaded studs 52 projecting from the side of ase 1 Obviously, a machine of the same arrangement as that illustrated may be used for grinding and inishing spiral gears or simi-l lar gearing whose elements have their axes disposed at rightangles So, too, the machine admits of considerable"modification without departing from the invention. rlheretore, I do not wish to be limited to the specific construction and arrangement shown.

That l claim is:

1. In a machine of the class described, means for holding mated gears to be ground in correct working relation, a set of master gears in duplication of the gears to be ground, saidv master gears meshing free of back lash, means for positively driving the master driving gear and the driving gear to be ground simultaneously and at the same velocity, and means actuated by the master driven gear for positively driving the driven gear to be ground simultaneously and vat the same velocity with said master driven gear.

2. In a machine of the classdescribed, means for holding mated gears to be ground in correct Working relation, a set of master gears in duplication of the gears to be ground, said master gears meshing free of back lash, means for positively driving the master driving gear and the driving gear to y means tor moving said gears to be ground into closer mesh.

3. In a machine for grindinor character described, a pair ott? rotary 'gear carriers, means for positively rotating said gear Carriers at the same velocity, a master gears Qt' the.

driving'gear fixed on one of said carriers,

said other carrier being adapted to receive a duplicate of the driving gear to be ground, a third rotatory gear carrier, amaster driven gear fixed on said third carrier in mesh with said masterdriving gear free of back lash, said third gear carrier being adapted to-receive a duplicate of the driven gear to be ground so asto mesh with said driving gear to be ground.

4. ln a machine for grinding gears of the character described, a pair of rotatory gear carriers, means for positively rotating said gear carriers at the same velocity, a 'master driving gears fixed on one of said carriers, said other carrier being adapted to receive a duplicate of the driving gear to be ground, a third rotatory gear carrier, amaster driven gear fixed on said third carrier in mesh with said master driving gear tree of back lash, said third gear carrier being adapted to receive a duplicate of the driven gear to be ground so as to mesh with said driving gear to be ground, and means for moving the gears to be ground gradually into closer mesh.

5. A machine for grinding worm gearing, comprising a master worm and Wormwheel meshed to run Without back lash, means for holding v a Worm and' Wormwheel to be ground in correct Working position in parallel relation to said master 6. A machine for grinding gears of the.

character described, comprising means for holdlng a set of gears to be ground 1n cor-V rect Workmg relation,` a set of accurately formed master gears iny duplication of the gears to be ground, external means for driving the driving gears of both sets simultaneously and at the same velocity, and means operated by the master driven gear for positively driving the driven gear to be ground .simultaneously and at the same velocity.

7. In a I machine of the character described, a pair of parallel rotatory gear carriers, a set of gears for rotating said carriers Witliout back lash and at the same velocity, a third gear carrier Whose axis is disposed at right; angles to the axes of said first mentioned gear carriers, a master driving gear on'one of said first mentioned gear carriers, a master driven gear on said second mentioned gear carrier, said gears being meshed so as to run Without back lash, a driving gear on the other` of said first mentioned gear carriers toy be ground, a driven gear on said second mentioned gear carrier to be ground in mesh With the driving gear to be ground, and means for maintaining an abrasive material in contact With the cooperating faces'of said gears to be ground.

`8. In a machine of the character de# scribed, a rotatory shaft having a master driving gear thereon, a shaft disposed at right angles to said rst mentioned shaft and 4having a master driven gear' thereon meshing With said master driving gear so as to run Without back lash, a driven gear to be ground on said second mentioned shaft, a shaft `adjustably mounted in parallel relation to said first mentioned shaft,`

a driving gear to be'ground on said adjustably mounted shaft, and means for positively rotating said first mentioned shaft and said adjustablymounted shaft simultaneously and at the same velocity.

9. In a machine of the character described, a rotatory shaft, a master gear thereon, a shaft disposedat an angle to said first mentioned shaft,l a master gear on said second mentioned shaft in mesh with said first mentioned master gear so as to run Without backlash, said second mentioned shaft being adapted to receive a gear to be ground, a hinged frame, a rotatory gear holder journaled in said' frame and adapted to receive a gear to be ,ground in mesh With said rst mentioned gear to be ground, means` for moving .said frame tobring the gears to be 4ground into closer mesh, and means for positively rotating said first mentioned shaft and said Vgear holder `simultaneously and at the same velocity.

10. In a machine for grinding. Worm gears, means` for holding the Worm and Worm-Wheel to be ground in`- correct Work- Worm and vWorm-Wheel for driving them independently butv simultaneously and at their correct Velocity ratio.

l1. In a machine for, ygrinding worm gears, means for holding the Worm and Worm-Wheel to be ground in correct Working relation, means external of said Worm and Worm-Wheel for driving them independently but simultaneously and at their correct velocity ratio, and means for maintaining an abrasive material in contact with.

,ing relation, and means external of said' ioo justably supported rotatory carrier adapted to receive a Worm to be ground in mesh With said Worm-Wheel to'be ground, duplicate driving gearsv on said first mentioned shaft and the carrier for the worm to be ground, and a driving pinion meshing With said-.duplicate driving gears so as 'to actuate them Without back lash.

.signed at Dama, Michiga, this ist dayof February, 1912. ROBERT B. WEAVER. Witnesses:

H, W. ALDEN, LEsLrE WILLIAMS. 

